Steer - Castrated bull. The lack of testicles allows for a lot less testosterone production which equates a fatter animal and tender meat. This will usually wind up on your plate as steak.

Dairy Cow - This is where you get your milk unfortunately. They lactate 300 days out of a year, always pregnant. Their meat is very tough. Usually winds up as ground beef after it kicks the bucket or is of no further use. Ground up because it's just softer that way.